what does it all mean?

Last night I had a dream that Arthur's brother, William, went crazy. He was chasing everything around the house and killing it, including the pets. He cornered Arthur and my brother, Mason, in a room, I left for 5 seconds to grab the phone to call 911 and when I returned he had stabbed both of them in the chest. I started screaming hysterically. When I looked down from the second story window I was in, he had Blitz.

Then Paul called and I woke up.

Arthur is considering moving in with his brother next month. Perhaps there are some things he should know.